Field of the Invention
This invention pertains in general to the field of embolic protection devices. More particularly the invention generally relates to systems and methods for cerebral protection by deflection of embolic debris, such as during an endovascular procedure, in particular on the heart, in some embodiments.
Description of Prior Art
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Endovascular procedures are being used more and more frequently to treat various cardiac and vascular surgical problems. Blocked arteries can be treated with angioplasty, endarterectomy, and/or stenting, using minimally invasive endovascular approaches. Aneurysms can be repaired by endovascular techniques. Another use for endovascular surgery is the treatment of cardiac valvular disease. Valvuloplasties are done endovascularly and percutaneous valve replacement is becoming an established procedure. Transcatheter Aortic Heart Valve (TAVI) is a procedure involving a collapsible aortic heart valve that can be manipulated into place with minimally-invasive techniques.
Cerebral embolism is a known complication of such endovascular procedures, and other cardiac surgery, cardiopulmonary bypass and catheter-based interventional cardiology, electrophysiology procedures etc. Embolic particles, may include thrombus, atheroma and lipids, plaque found in the diseased vessels and valves that is dislodged and results in embolization. Embolic particles may become dislodged by surgical or catheter manipulations and enter the bloodstream. Dislodged embolic particles can thus embolize into the brain downstream. Cerebral embolism can lead to neuropsychological deficits, stroke and even death.
Prevention of cerebral embolism benefits patients and improves the outcome of these procedures. Embolic protection devices should be compatible with the endovascular procedures, and for instance not hinder passage through the aortic arch to the heart.
Various embolic protection devices are known in the art.
Some embolic protection devices are disclosed in WO 2012/009558 A2, or WO 2012/085916 A2, which are incorporated herein in their entirety for all purposes. However, these devices may provide iatrogenic damage to the vessels in which they are positioned, e.g. by bows or arms extending into the side vessels of the aortic arch. The bows or arms provide anchoring in the arch, but increase risk of scraping off embolic particles, in particular from around the ostia to the side vessels. The devices also have a rather high profile in the aortic arch, limiting the endovascular procedures to be performed through the arch.
More advantageous low profile planar devices for embolic protection of side branch vessels of the aortic arch have for instance been disclosed in WO 2010/026240 A1 or are described in international patent application number PCT/EP2012/058384, which was published after the priority date of the present application as WO2012152761, and which all are incorporated herein in their entirety for all purposes.
In WO2012009558 an umbrella shaped deflection device is disclosed having a delivery wire connected to a central hub. The device is delivered through one of the side vessels to be protected and the guide wire remains in the side vessel. The guide wire connected to the central hub may be pulled back to put the device into position. However, this leads potentially to so-called wind sucker disadvantages due to the movement of the aorta with every heart beat. Debris may collect at the edge of the umbrella and be occasionally sucked into the side vessel as the hub is locked when pulled back and does not follow the aorta movement sufficiently well. Embolic protection efficiency is thus not optimal of the devices described in WO2012009558.
In US2004/0073253A1 an embolic particle capturing is disclosed, which is positioned in the aortic arch via a femoral approach. A hoop at the distal end of the device has a larger diameter than the aorta at the implantation location and presses radially outwardly against the aortic wall. The device blocks the aortic arch when in position and does not allow for index procedures to be performed in a femoral approach.
In WO00/43062, a flow divider is described which compartments the aortic arch and seals the side vessel space from the latter. An embolic filter may be applied to blood perfused to the side vessel space, or filter the blood in the aortic arch in addition to the flow divider. However, the device is complicated as no blood can flow directly from the aortic arch to the side vessels and extracorporeal blood handling devices are needed.
In US 2002/0133115A1 methods for capturing medical agents are provided including magnets.
The devices of the state of the art may however be further improved. One issue is that blood, that may include embolic particles, may impair efficiency of the devices by bypassing across the device at the periphery thereof to the carotid arteries due to insufficient sealing at the periphery.
“Sailing” of the devices in the high pressure bloodstream ejected out of the heart is another issue avoided by examples of the present disclosure. The devices shall provide a stable positioning of the deflection device in the aortic arch.
Hence, notwithstanding the efforts in the prior art, there remains a need for a further improved embolic protection devices of the type that can permit endovascular procedures, in particular of the heart, while protecting the cerebral vasculature during the procedures.